Cartilaginous Fish vs Bony Fish
Ob hom ntses no ua tau yuav luag txhua hom ntses nyob hauv ntiaj teb. Ua ke, muaj 28, 000 hom ntses pob txha thiab cartilaginous. Lawv nthuav tawm ntau qhov sib txawv ntawm lawv uas ua rau nws txaus siab los ua qhov sib piv.
Ntses Cartilaginous
Hauv cov ntses cartilaginous, nws yog pob txha pob txha pob txha es tsis yog pob txha raws li lub npe qhia. Sharks, skates, rays yog qhov piv txwv zoo rau cov ntses cartilaginous. Tsis muaj kev sib txuas ntawm lawv lub puab tsaig sab sauv thiab pob txha taub hau, kom lawv txav tau nws tus kheej. Lub pob txha taub hau muaj 10 qhov chaw cartilaginous thiab lawv muaj daim tawv muag los tiv thaiv lawv ob lub qhov muag. Cartilaginous ntses tsis muaj tav thiab tsis muaj pob txha. Yog li ntawd, kev tsim cov qe ntshav liab tshwm sim hauv tus po. Dermal denticles npog tag nrho cov tawv nqaij thiab cov zoo li cov qauv ntawm peb cov hniav. Lub qhov ncauj yog sub-terminal, i.e. nyob rau hauv ventrally nyob rau hauv cartilaginous ntses. Lawv tsis muaj operculum los npog cov gills, thiab muaj 5 - 7 gill slits tseem qhib txhua lub sijhawm. Lawv caudal fin tsis sib luag, thiab ob lub lobes ntawm tus fin yog qhov loj me. Lwm qhov nthuav tshwj xeeb yog tias lawv cov pectoral fin yog sib npaug rau qhov ntev ntawm lub cev, uas pab kom lawv sib npaug ntawm lawv lub cev tsis yog muab lub zog ua luam dej los ntawm kab dej. Lawv lub cev lub cev hnyav nrog rau lub siab uas muaj roj ua kom muaj zog tiv thaiv lub cev hnyav. Lawv qhov hnyav hnyav tuaj yeem tsoo lub cev sab hauv sab nraum dej (xws li shark). Lawv tawm urea raws li cov khoom pov tseg nitrogenous. Lawv yog cov fossils nyob, vim tias cov ntses cartilaginous pib hloov zuj zus ua ntej 420 lab xyoo, thiab tam sim no muaj ntau dua 970 hom nyob hauv hiav txwv.
Bony Fish
Raws li lawv lub npe qhia, lawv muaj pob txha pob txha, uas yog calcified thiab ossified. Lawv lub puab tsaig sab sauv txuas nrog pob txha taub hau, thiab pob txha taub hau muaj 63 lub pob txha me me. Bony ntses khaws lawv lub qhov muag ib txwm qhib, vim lawv tsis muaj daim tawv muag. Lawv muaj cov nplai npog thoob plaws lub cev, thiab lub caudal fin yog symmetrical. Tsis tas li ntawd, lawv cov pectoral fin yog perpendicular mus rau longitudinal axis ntawm lub cev. Bony ntses muaj gas-filled ua luam dej zais zis, uas yog pab tau rau buoyancy. Lawv muaj lub ntsej muag los npog cov gills hu ua operculum. Bony ntses tawm ammonia raws li lawv cov khoom pov tseg nitrogen. Bony ntses nyob hauv dej hiav txwv thiab dej ntsev, thiab muaj ntau tshaj 27,000 hom ntawm lawv. Ntxiv mus, cov ntses pob txha muaj ntau tshaj li ib nrab ntawm tag nrho cov vertebrate hom nyob rau hauv lub ntiaj teb no.
Qhov txawv ntawm Cartilaginous Fish thiab Bony Fish
| ntses cartilaginous | Bony ntses |
| Ntau tshaj 970 hom, thiab nyob hauv ib puag ncig hauv hiav txwv xwb | Ntau tshaj 27,000 hom, thiab nyob hauv cov dej tshiab thiab dej ntsev |
| Cartilaginous endoskeleton | Bony endoskeleton |
| Qhia gill slits | Operculum los npog gills |
| Lub puab tsaig sab sauv txav ntawm nws tus kheej, vim nws tsis txuas nrog pob txha taub hau | lub puab tsaig sab sauv txuas nrog pob txha taub hau |
| Dermal denticles npog lub cev | Ncaj npog lub cev |
| Asymmetric caudal fin | Symmetric caudal fin |
| Pectoral fin yog sib npaug rau qhov ntev ntawm lub cev | Pectoral fin yog perpendicular mus rau longitudinal axis ntawm lub cev |
| Roj puv siab rau buoyancy | gas-filled zais zis rau buoyancy |
| Ib txwm ib lub qhov ncauj sub-terminal | Lub qhov ncauj tuaj yeem yog lub davhlau ya nyob twg lossis lub davhlau ya nyob twg lossis lub davhlau ya nyob twg raws li qhov chaw nyob hauv kab dej |
| Nitrogenous pov tseg yog urea | Nitrogenous pov tseg yog ammonia |
